As computing systems, such as desktop computers, laptop computers, servers, and the like, have increased in processing speed, power dissipation of system components has become a concern. In fact, failure to adequately heat sink components such as processors and memory modules results in elevated temperatures within the housing or cabinet in which the components reside. For example, failure to adequately heat sink or ventilate a server, which may have several racks of processors on printed circuit cards, may result in a temperature that exceeds the recommended operating temperatures of various components within the server housing. Such a situation may result in thermal shut down of the system or throttling of various components within the system.
Throttling system processors has been used to limit system power dissipation, however, memory subsystem power dissipation has been increasing. The introduction of fully buffered dual in-line memory modules (FB-DIMMs) has resulted in cumulative power dissipation rates that, on some platforms, exceed the processor power utilization. One of the capabilities introduced in the Advanced Memory Buffer (AMB) that is used by the FB-DIMMs is the ability to throttle the individual DIMMs. In addition, thermal sensors have been embedded on DIMMs, thereby resulting in DIMM temperature feedback.
Throttling system components such as processors or memory effectively reduces the operating speed of the throttled component, which, in turn, reduces the overall operating speed of the system having throttled components. Thus, under thermal throttle conditions, the end-user will see moderate to significant general slow-down of their systems.
Additionally, in some circumstances, even throttling of components, such as memory and/or processors is insufficient to address thermal issues encountered by a computing platform. For example, high density computing nodes having limited cooling surface areas and significant computing power per square meter, as well as very high power dissipation on subcomponents (e.g., in the range of 10 Watts/FB-DIMM) results in situations making the thermal environments a critical situation. In such systems, a change to the cooling environment, such as a ventilation failure, may result in thermal runaway scenarios during which even full throttling of all the memory and processor components is insufficient to keep the platform in an operating state.